1. Field of the Invention
The present invention relates to a resin solution and a method of forming a protection layer, and more particularly to a resin solution and a method for forming a protection layer including an organic solvent and a resin.
2. Background of the Invention
Semiconductor devices may be vulnerable to external conditions. Therefore, semiconductor devices are manufactured in clean environments. Upon entry into non-clean environments, it may be necessary for a packaging process to be applied to a semiconductor device to ensure its continued protection. The semiconductor device may be encapsulated by a packaging process to protect the semiconductor device from the external environment. The packaging process may include forming an epoxy molding compound around the semiconductor device.
Prior to the packaging process, a semiconductor device may be covered with a passivation layer and/or a polyimide layer. These layers may assist in maintaining the integrity of the semiconductor device during the packaging process.
The polyimide layer may act as a buffer layer to alleviate stress generated during the packaging process. The polyimide layer may also act as a protection layer against alpha particles which may penetrate the semiconductor device. Alpha particles may have a negative effect on the electric charges created or induced in a depletion layer of a PN junction of the semiconductor device.
In semiconductor memory devices, memory cells may be comprised of data storage elements connected to the PN junction. Alpha particles, which reduce the electric charges of the PN junction, can thus decrease the reliability of semiconductor memory devices. In the case of volatile memory devices, such as a DRAM memory cell, the data storage element may correspond to a cell capacitor and data (charge) stored in the cell capacitor may be lost due to the α-particles.
Conventionally, a polyimide layer is formed from an organic solvent and a polyamic acid. The organic solvent and the polyamic acid may be applied to the semiconductor device and then baked at a temperature of at least 280° C. The baking of the polyimide layer should be processed at a temperature as low as possible to so as to not deteriorate the reliability and/or refresh characteristics of the semiconductor device.
A cross-link reaction must occur between the organic solvent and the polyamic acid to form the polyimide layer. However, a cross-linking reaction occurs only at high temperatures. Using-conventional methods, as described in U.S. Pat. No. 5,554,684, this is only possible at temperatures above 280° C. At temperatures above 280° C., there exists the possibility of creating deficiencies within the semiconductor device. These deficiencies can reduce the yield of semiconductor fabrication.